I completely switched to Mac about 5 years ago. I'm also considering the new 13" Macbook since my buddy can help w/ the educational discount.
That being said, I agree that iPhoto can be mind numbingly confusing. Honestly, w/ my photo library, I manually manage it on 2 network drives (Time Capsule and USB HDD on another Airport Extreme), similar to you mentioned. The problem w/ iPhoto (similar to iTunes) is that it can sometimes do too much. If you let it organize your photos, your directory structure will be complete obliterated and you'll never get it back to it's original state. I had a similar problem w/ iTunes and thousands of pre-organized MP3 files. I've had to get over that over the course of several years... My STRONG recommendation before you attempt to use another photo organization too, back up your photo library to another HDD to preserve your directory structure. That way you'll have a recovery method if you don't like what iPhoto (or similar) will do to it.
Now I haven't had a chance to use iLife 09 yet. There's a bunch of cool features there but frankly it's only installed on a Hackintosh that isn't powerful enough for all the features of iPhoto 09. But it might be worth checking out.
Another thing to consider is an off site backup of photos. I am one of those victims you hear about, who lost a bunch of photos from an HDD crash. I was moving files between my 2 backups and my photo archive drive crashed. (The drive is currently unrecoverable sans an $$$ service.) I have backups on various websites but it's a pain. Now I use something called JungleDisk. I love it because I have 13GB of photos backed up at Amazon for about $2.50/mo. Not bad IMHO and I don't even have to manage any of it.
http://jungledisk.com/
